Are We Too Clean or Not Clean Enough?
Antimicrobials Scrutinized for Their Role in Handwashing Compliance, Antibiotic Resistance
By Kelly M. Pyrek
As fastidious healthcare professionals continue to lather up after patient contact, they may be asking themselves, how clean is too clean? Or are we not clean enough? While infection control practitioners struggle to achieve total handwashing compliance among increasingly rushed healthcare workers (HCWs), they realize that being too clean is hardly the issue when many HCWs engage in a quick rinse-and-go approach to hand antisepsis.
While most protocols call for 30 to 60 seconds of handwashing, the Healthcare Infection Control Practices Advisory Committee (HICPAC) discovered HCWs fall far short of this standard. HICPAC says eight out of 11 studies that evaluated the average duration of handwashing by HCWs, revealed averages of less than 15 seconds. Six of those studies reported averages of less than 10 seconds.1 Lack of handwashing compliance among HCWs can be attributed to everything from the avoidance of dermatitis to the belief that handwashing is not convenient.
Proponents of alcohol-based hand antiseptics say these products reduce microbial loads, are less time-consuming than handwashing, are more convenient than handwashing facilities, and are less irritating to the hands than soap and water. There has been no shortage of dialogue within the healthcare industry regarding hand hygiene, the role of antibacterial products such as alcohol-based agents, and the impact they have on so-called garden-variety bacteria as well as on the tougher multi-drug resistant pathogens. To help answer growing questions about the use of antimicrobial agents, the Centers for Disease Control and Prevention (CDC) has developed a draft hand-hygiene guideline recommending that waterless, alcohol-based agents may be used as surgical scrubs except when the hands are visibly soiled with bioburden.
According to Dr. William Jarvis, associate director for program development at the CDC's Division of Healthcare Quality Promotion, the draft guideline and allows alcohol-based gels and foams to be used for the initial scrub, as well as for use in between cases. The guideline adds that when organic matter or soil is present on the HCW's hands, a soap containing antimicrobial properties should be used with water.
Jarvis believes the use of antimicrobial agents simply helps HCWs be more scrupulous about their hand hygiene, even when staffing levels are low. A 1997 study charged that handwashing compliance rarely exceeds 40%, and that HCWs frequently attribute their failure to wash their hands due to limited time.2 The study calculated a time consumption for handwashing (40-80 seconds) as well as for the use of an alcohol-based hand disinfectant (20 seconds) in an ICU setting with 12 HCWs. Researchers concluded that given 100% compliance, handwashing consumed 16 hours of nursing time per day shift, while the use of alcohol-based hand disinfectants required 3 hours of time. They believe that handwashing may interfere with the delivery of patient care and partly explains low compliance rates; however, they say the alcohol-based hand disinfectants, with their speed and efficacy, allows for 100% compliance without interfering with the quality of patient care.
"Many of us in infection control and healthcare epidemiology believe hand hygiene is one of the most important and effective methods to reduce the transmission of pathogens in healthcare settings," Jarvis says. "Studies have shown HCWs wash their hands less than 50% of the time. One of the most common excuses is that handwashing facilities are not convenient. The use of waterless, alcohol-based hand hygiene agents will facilitate hand hygiene by making the capacity to perform hand hygiene immediately available to everyone."
Jarvis continues, "Studies that that use of these agents improves the compliance of HCWs with current handwashing recommendations. Furthermore, studies have shown these agents are very effective in reducing or eradicating the most common healthcare-associated pathogens. If we can improve healthcare worker hand hygiene compliance, we should be able to reduce the rate of healthcare-associated infections."
Jarvis admits that antimicrobial agents are not magic bullets against bacteria, but says they are an important tool in HCWs' arsenal against pathogens. "No handwashing agent kills or effectively removes all infectious agents," he adds. "However, these alcohol-based agents are very effective at reducing or eradicating the most common pathogens."
A 1999 study examined the effectiveness of an alcohol solution compared with standard handwashing procedures in clinical wards and intensive care units of a large public university hospital.3 Forty-seven HCWs were randomly assigned to wash their hands with soap and water, while others used an alcohol-based agent. The number of colony-forming units on agar plates from hand printing in three samples was counted. The average reduction in the number of colony-forming bacteria after hand hygiene was 49.6% for soap and water, and 88.2% for the alcohol-based agent.
In another study that compared an alcohol-based, waterless hand disinfectant with the standard soap/sink combination involved the observation of 1,575 potential hand hygiene opportunities within a 120-hour period in an ICU setting.4 The baseline handwashing compliance before and after patient contact was 9% and 22% for HCWs; observations after the introduction of the, alcohol-based hand antiseptic revealed higher handwashing rates. Compliance rose from 23% before and 48% after patient care with one hand-antiseptic dispenser for each patient bed.
Hand-sanitizer dispensers mounted in the hallways outside of patient rooms were nearly 30 times more likely to be used than dispensers inside the rooms, according to a five-month study conducted in two ICUs at the University of California, San Diego Medical Center.5 HCWs had been observed washing their hands in 39.6% of patient-contact situations. Two to six weeks after introducing an alcohol-based hand sanitizing gel as an alternative to soap-and-water handwashing, compliance rates rose to 52.6%.
Despite the CDC's draft guidelines, some HCWs wonder if alcohol-based agents are suitable as surgical scrubs. The Association of periOperative Nurses (AORN), in its "Recommended Practices for Surgical Hand Scrubs" guidelines, states, "An effective antimicrobial surgical hand scrub agent approved by the facility's infection control committee should be used for all surgical hand scrubs." While the AORN does not endorse specific hand-hygiene products, if they are considered to be surgical hand scrub agents, they should significantly reduce microorganisms on intact skin, contain a non-irritating antimicrobial preparation, be fast acting, and have a residual effect.
AORN's guidelines acknowledge that chlorhexidine gluconate products rank highest in residual activity and persistence, followed by iodophors and triclosan. They also say that in the appropriate concentrations of 60% and 70%, alcohol agents offer the most rapid and greatest reduction in microbial counts on skin.
While many healthcare professionals recognize the benefits of the use of antimicrobial agents, some express concern that the pervasiveness of these agents could trigger resistance. Some scientists believe the use of antibacterial-laced products in the home could compromise the battle against microorganisms in hospitals. While antibacterial agents have their place in a clinical setting, their indiscriminate use in the home could jeopardize individuals' ability to fight off bacterial infections. Scientists are concerned that antibacterial agents will select the bacteria resistant to them and become cross-resistant to antibiotics. Also, if these antimicrobial agents affect an individual's inherent microflora, they may affect the normal maturation of the body's immune system and hamper the body's ability to fight off infection.
Between 1992 and 1998, nearly 700 new antibacterial products flooded the marketplace, including such diverse items like window cleaners, plastic food-storage containers, underwear, and bedding. And with the introduction of the antimicrobial agent triclosan into numerous consumer hygiene products in 1995, Americans have been busy trying to rid their bodies and their lives of bacteria.
"The good news and the bad news is that people are so much more aware of germs," says Dr. Stuart Levy, professor of molecular biology and microbiology as well as director of the Center for Adaptation Genetics and Drug Resistance at Tufts University School of Medicine. He also is president of the Alliance for the Prudent Use of Antibiotics (APUA). "At the same time we've also seen the emergence of resistance to new antibiotics.
"I think the overuse of antibacterial products is a misuse of them as agents to prevent transmission of disease, and it will ultimately do these products a disservice," Levy added. "The link from antimicrobial agents to antibiotic resistance tells us that the downside to the entire issue is much bigger than resistance to the drugs themselves. I think these antibacterial projects have a legitimate place in hospitals, where they have been remarkable in their efficacy. Studies tell us these alcohol-based antimicrobial products are doing an excellent job of killing bacteria and can be less irritating to the skin than handwashing. On the other hand, in the home, where we are not dealing with large numbers of potentially bad bacteria, these products can disrupt the presence of beneficial flora. In our everyday life, washing with soap and water and having these microbes go down the drain is all you have to do. You don't need the alcohol-based products in the home, especially those that have residues that stick around for a long period of time."
Levy says that while antibiotics are critical to the treatment of bacterial infections, because of the years of overuse and misuse of these drugs, targeted bacteria have developed antibiotic resistance. He writes, "The relatively recent increase of surface antibacterial agents or biocides into healthy households may contribute to the resistance problem. The antibacterial substances added to diverse household cleaning products are similar to antibiotics in many ways. When used correctly, they inhibit bacterial growth. However, their purpose is not to cure disease but to prevent transmission of disease-causing microorganisms to non-infected persons. Like antibiotics, these products can select resistant strains and, therefore, overuse in the home can be expected to propagate resistant microbial variants."6
Levy continues, "We hear about 'superbugs' and deadly viruses. Germs have become the buzzword for a danger people want to eliminate from their surroundings. In response to these messages, people are buying antibacterial products because they think these products offer health protection. Bacteria are not about to succumb to this deluge, however. Through mutation, some of their progeny emerge with resistance to the antibacterial agent aimed at it, and possibly to other antimicrobial agents as well."
Countless cases of emerging multi-drug resistant bacteria, or "superbugs," have been reported, and public health officials and HCWs are sounding the alarm. According to experts at the Mayo Clinic, strains of at least three bacterial species have demonstrated startling degrees of antibiotic resistance, including vancomycin-resistant Enterococcus (VRE). Other superbugs include methicillin-resistant Staphylococcus aureus (MRSA), vancomycin-intermediate Staphylococcus aureus (VISA), and vancomycin-resistant Staphylococcus aureus (VRSA)
Levy says these superbugs have thwarted more than 100 antibiotics due to the bacteria's ability to create proteins that protect them from the drugs, and they are able to multiply under the shield of widespread antibiotic use. Levy writes, "Although antibiotics are needed to control bacterial infections, they can have broad, undesirable effects on microbial ecology. That is, they can produce long-lasting change in the kinds and proportions of bacteria not only in the treated individual but also in the environment and society at large. (Antibiotics) should thus be used only when they are truly needed. Promoting resistance in known pathogens is not the only self-defeating activity of antibiotics. When the medicines attack disease-causing bacteria, they also affect benign bacteria in their path. They eliminate drug-susceptible bystanders that could otherwise limit the expansion of pathogens, and they simultaneously encourage the growth of resistant bystanders."7
Levy stands firm when he says antibacterial agents will have an impact on environmental flora and on resistance emergence. The CDC's Jarvis disagrees. "Improved hand hygiene should reduce the prevalence of transmission of these superbug pathogens," he says. "There is no evidence that the use of such agents results in increased emergence of resistant strains."
Many believe that the resistance problem should be blamed on the blatant misuse of antibiotics. More than 133 million courses of antibiotics are prescribed by physicians each year to non-hospitalized patients, while 190 million doses a day are administered in hospitals. While the crisis of antibiotic resistance may have only recently captured the public's attention, HCWs have been monitoring developments for decades. As fast as antibiotics have been developed, history proves that bacteria have found ingenious ways to thwart them. In 60 years, the medical world has been introduced to penicillin, methicillin, ampicillin, cephalosporins, cefoxitin, cefotaxime, amoxicillin, imipenem, and aztreonam.
The battle waged between humans and bacteria, as James Wilde, MD, assistant professor of emergency medicine at the Medical College of Georgia, described in recent research, may lean toward the microbes' favor simply because of the sheer number of them and their ability to replicate themselves--especially if just one mutant microorganism survives a course of antibiotics.
Wilde writes, "The struggle between man and microbe can be compared to a war of attrition, but in this war technology is losing the arms race with evolution. We can postpone our day of defeat by using our resources wisely. Unfortunately, the rate of attrition has been increased by some physicians who are indiscriminate in their use of antibiotics."8
In essence, antibiotics may actual help train "superbugs" on how to adapt their cellular structure to become impervious to future attacks by the same drug. There are several mechanisms that assist in the creation of resistant strains. If a bacterium can produce an enzyme that alters the antibiotic, it also may alter the structure of the drug enough to prevent it from attaching to its binding site.9 Second, the binding site of the antibiotic can be altered, thus making it unrecognizable to the drug and the antibiotic loses its effect-the exact way that Streptococcus pneumoniae eluded penicillin.10 Third, the bacteria can develop ways to deny the drug access to the binding site, including developing efflux pumps that remove antimicrobial agents from the intracellular environment.11
Wilde says that the elemental mechanism for the transmission of resistance is the selection of naturally resistant mutants. If a bacterial population is exposed to an antibiotic, most of the bacteria will be susceptible and die. However, minute numbers of non-susceptible bacteria will survive and multiply to fill the void left by the susceptible bacteria. Broad use of an antibiotic could lead to the development of resistant populations of organisms, and this bacteria could be spread to unaffected people via contact with a contaminated environment and multiply to levels of clinical significance. Wilde believes that the only ways to slow the spread of resistance is to limit the use of antibiotics, in that the less frequently a bacterial population is exposed to a drug, the less likely resistance will be developed.
Zyvox was introduced into the marketplace by Pharmacia Corp. last year, and physicians jumped at the chance to use the first new antibiotic of its kind in more than 30 years. Zyvox, known as a linezolid, is a synthetic chemical that stops bacteria from synthesizing protein, which in turn halts their growth and the body's immune system can destroy them. However, in April, scientists at the University of Illinois, Chicago College of Medicine reported three cases of Zyvox-resistant enteroccoci infection, while in July, researchers at Harvard Medical School reported a staph infection that was not vulnerable to the new drug. S. aureus, considered to be one of the strongest bacteria and the leading cause of infections in hospitals, also is developing resistance to the potent antibiotic vancomycin.12 In efforts to slow resistance, the CDC advises physicians to refrain from using vancomycin unless absolutely necessary.
While the jury is still out on antimicrobials' influence on antibiotic resistance, and an increasing number of antimicrobial products debut in the healthcare market, old-fashioned hand antisepsis remains the gold standard for many healthcare professionals.
"Handwashing should be the first and prime root of infection control," Levy emphasizes. That doesn't sound terribly profound, but vigorously washing the hands with soap and water is still the best way to combat bacteria. If someone is still worried about opportunistic microorganisms affecting an immunocompromised patient, then you may want extra protection through the use of an antibacterial. My message to infection control practitioners is that you are the stalwarts, you are the ones on the front lines who set the standards on good hygiene in the healthcare setting and in the home."
Surgical Incise Drapes With Antimicrobials Support the Fight Against Infection
By Kelly M. Pyrek
As dialogue continues over the use of alcohol-based hand disinfectants (see accompanying story), antimicrobial agents have long served the role of combating the transmission of bacteria in the operating room.
"With any surgery, the major concern is infection, and it's the No. 1 reason for a procedure to fail," says Dave Padget, owner and COO of Medical Concepts Development. The use of antimicrobials is just one of many things you have to do to maintain antisepsis. The best way to prevent infection is to prevent bacteria from getting into the wound, because even if you kill them, they're still a pathogen."
"Drapes which have these antimicrobial properties are a good way to supplement antisepsis techniques in the OR," says Carol Pack, product manager for Microtek Medical, Inc., manufacturer of surgical drapes and fluid-control products. "Surgical incise drapes are used to reinforce what the skin-prep process has done to eradicate microorganisms. A lot of these pathogens are carried by fluids or travel through the air, and incise drapes help keep the prepped area intact and protected from transient bacteria."
Pack adds that a drape with an antimicrobial agent incorporated into the polymer material provides comprehensive antisepsis. "This saturation from top to bottom further enhances protection from microbes. The drapes feature triclosan in a concentration level that provides an effective kill rate in the zone of inhibition."
To avoid using antimicrobials as a crutch, Padget says other infection control measures should be taken to reduce the number of bacteria these antimicrobials must destroy.
"You're not going to prevent all the bacteria from entering the surgical site, but every little place where you can reduce the number of bacteria, statistically, the better chance you have of it not colonizing" Padget says.
Padget continues,"Since antimicrobials only affect external contamination whereas antibiotics work on bacteria already in the cavity, the biggest concern in healthcare is resistance to your antibiotic regime." As a manufacturer of iodine-based antimicrobial incise drapes, Padget says Medical Concepts Development endeavored to create a product that would not succumb to resistance. He says many antimicrobials, such as quinine ammonia, 60-70% ethyl and isopropyl alcohol, triclosan, and chlorahexidine gluconate, are hostile to bacteria. While an excellent kill rate is desirable, Padget says it can trigger the kind of behavior by a bacteria that leads to the development of resistant strains.
Padget says that povidone iodine is one of the most widely accepted perioperative antimicrobial skin preparations because it is less toxic to tissue. "The reason iodine is used so extensively in surgery is because it doesn't act the same way as chlorine or alcohol," Padget says. "Iodine is not immediately hostile to bacteria."
Padget explains that a bacteria's cellular structure is much like a human's in that it has iodine receptors. Iodine is needed by the body in order to produce thyroxin, which regulates cellular metabolism. He says the iodine is taken in by the cellular wall and passes through to the cytoplasm where it affects the genetic makeup of the cell. The elemental iodine, absent thyroxin and therefore considered to be an antimicrobial agent, will alter the DNA and incapacitate the cell's ability to reproduce. Without this ability to multiply, the bacteria dies and colonization is prevented.
"Resistance forms when bacteria go into dormancy because they are confronted with a hostile environment," Padget says. "To my knowledge, there is no known resistance to iodine antimicrobials."
Microtek's Pack agrees. "We've seen very little when it comes to microorganisms building resistance to the antimicrobial agents used in surgical incise drapes," she says. "While sensitivities to some antimicrobials, like iodine, may develop, these agents are extremely effective in their fight against infection."
"The rationale for using drapes with antimicrobial properties is that while you can't sterilize the skin, you can use a pre-op prep but there will still be bacteria in the hair follicles, sweat glands, and on the surface of the skin," Padget says. Antimicrobial incise drapes provide a polymeric shield through which bacteria cannot surface, reducing the number of germs that are rubbed or irrigated into the surgical site. Drapes create a sterile surface, and the antimicrobial properties of the adhesive immobilize bacteria that would normally surface and transmigrate. If you can prevent bacteria from traveling through the air or swimming in fluids, they won't get to the surgical site. This is important because the longer the procedure, the more critical it is to fight bacteria."
|"Are We Too Clean or Not Clean Enough?"|
by Kelly M. Pyrek
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